General approach to the understanding the electronic structure of graphene on metals

TL;DR

This paper introduces a general approach to understanding how bonding mechanisms affect the electronic structure of graphene on various metal substrates, demonstrated through case studies on Al(111), Ni(111), and Cu(111).

Contribution

It provides a unified framework linking bonding strength to electronic structure modifications in graphene/metal systems, clarifying long-standing debates.

Findings

Dirac cone preserved in weakly bonded graphene on Al(111)

Dirac cone destroyed in strongly bonded graphene on Ni(111)

Electronic structure of graphene/Cu(111) explained by the approach

Abstract

This manuscript presents the general approach to the understanding of the connection between bonding mechanism and electronic structure of graphene on metals. To demonstrate its validity, two limiting cases of the "weakly" and "strongly" bonded graphene on Al(111) and Ni(111) are considered, where the Dirac cone is preserved or fully destroyed, respectively. Furthermore, the electronic structure, i. e. doping level, hybridization effects, as well as a gap formation at the Dirac point of the intermediate system, graphene/Cu(111), is fully understood in the framework of the proposed approach. This work summarises the long-term debates regarding connection of the bonding strength and the valence band modification in the graphene/metal systems and paves a way for the effective control of the electronic states of graphene in the vicinity of the Fermi level.